Project Year 2015

Reduced feed loss

Researchers have developed a processing aid that act as a nutrient and binder in extruded fish feed.

This can contribute to reducing feed loss in the aquaculture industry and make feed production more energy-efficient. The processing aid is a protein-based solution that can be produced from marine raw materials or plant protein.

In his doctoral thesis Tor Andreas Samuelsen at Nofimas Feed Technology Centre in Bergen studied how loss in feeding systems can be reduced by taking action during feed processing. Nofima has estimated that the loss in feeding systems constitutes a yearly additional expense of around NOK 40 to 200 million. To reduce loss, the feed must have uniform and high physical quality.

The main objective of the doctoral project was to divide fishmeal into components, identify which of these influences the extruder, and determine their significance for the physical properties of the final fish feed.

The components with a positive effect on the extrusion process are water-soluble low molecular weight proteins (small peptides and amino acids). These proteins are pressed out together with water during production of fish meal and have a high nutritional value. Such proteins will make processing from raw material to pellet easier and also act as a binding agent. Researchers have shown how the processing aid works during production of fish feed and which type of proteins that have the desired effect on physical feed quality.

“This allows us to exploit water-soluble low molecular weight proteins better, both to ease processing from raw material to pellet, and as a binding agent and nutritional component,” Samuelsen says.

The processing aid has several of the same properties as water, and can thus reduce energy consumption in the feed process.

Knowledge from the doctoral project may also contribute to reduced reprocessing of feed and fewer customer claims due to poor physical feed quality.